I'm glad you came here, morshed jahan.

Let me shed some light on why there are variations of report between Cash basis and Accrual basis in QuickBooks Online (QBO).

When you run the Balance Sheet report using the Cash basis accounting method, the transactions appear will be those you have received cash and expenses if you have paid cash.

The Accrual basis on the other hand, recognizes revenue when it's earned, and expenses when they're billed even when they are not yet paid.

For more information about the Balance Sheet report, check out this article: What is a Balance Sheet report?

Be sure to get back to me if you have additional questions. It would be my pleasure to help. Have a good one!